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This study was designed to investigate the effect of cholestyramine on the formation of pigment gallstones in high carbohydrate diet-fed hamsters and whether that effect occurred because of cholecystokinin action. Forty seven hamsters were divided into three groups: group I(n = 16) was fed on normal rodent chow(43% carbohydrate), group II(n = 14) was fed on a high CHO diet(65% carbohydrate), group III(n = 17) was fed on a high CHO diet containing 4% cholestyramine. Gallstones developed in 0% of group I, 42.9% of group II and 5.9% of group III(P < 0.05, group II vs III). To evaluate the chronic status of cholecystokinin level, the wet weight of pancreas and the average area of pancreatic acinar in microscopic high power field were measured. There was no significant difference between group II and group III in pancreatic weight and average area of pancreatic acinar(P > 0.05). In gallbladder bile analysis, there was also no significant difference between group II and group III in cholesterol, phospholipid, total calcium, total bilirubin and bile acid levels. In conclusion, cholestyramine decreases the frequency of pigment gallstone formation in high CHO diet-fed hamsters, but it is not clear whether the mechanism of cholestyramine decreasing the gallstone formation is due to the action of cholecystokinin.  相似文献   
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Only rarely is renal cell carcinoma encountered in a horseshoe kidney. This is a case report on renal cell carcinoma in a horseshoe kidney, in which superselective renal artery embolization was performed preoperatively. CT and digital subtraction angiography revealed a horseshoe kidney with a 3-cm tumor in the left side. Superselective renal artery embolization of the tumor was performed as a prerequisite procedure for the organ-preserving surgery of simple enucleation. Preoperative superselective renal artery embolization can be an effective tool to facilitate organ-preserving surgery in a horseshoe kidney.  相似文献   
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PURPOSE: The aim of this prospective study was to ascertain the incidence of minor complications after mandibular third molar surgery and to predict the risk of skin ecchymosis or mucosa petechiae related to the usage of an absorbable gelatin sponge. PATIENTS AND METHODS: One hundred and four patients subjected to surgical extraction of horizontally impacted lower third molars were selected and investigated by means of questionnaires and clinical examinations. The independent sample t test was used for numeric variables. The chi-square test was used for logistic variables to determine the association between variables, and thereafter stepwise logistical regression was used. RESULTS: The older group (> or = 30 years old), with deeply impacted teeth, and long operation times (> or = 10 minutes) were shown to have significantly higher swelling than the other groups (P < .05). The patients who had deeply impacted teeth or long operation times were shown to have significantly higher VAS scores compared to short operation times (P < .05). The use of an absorbable gelatin sponge in the extraction socket significantly decreased postoperative swelling, mucosal petechiae, and skin ecchymosis (P < .05). CONCLUSION: The clinical variables related to postoperative bleeding disorder, pain, and trismus were identified. The insertion of an absorbable gelatin sponge into the extraction socket was found to be a very useful method to prevent postoperative bleeding problems.  相似文献   
175.
Quantifying both arterial cerebral blood volume (CBV(a)) changes and total cerebral blood volume (CBV(t)) changes during neural activation can provide critical information about vascular control mechanisms, and help to identify the origins of neurovascular responses in conventional blood oxygenation level dependent (BOLD) magnetic resonance imaging (MRI). Cerebral blood flow (CBF), CBV(a), and CBV(t) were quantified by MRI at 9.4 T in isoflurane-anesthetized rats during 15-s duration forepaw stimulation. Cerebral blood flow and CBV(a) were simultaneously determined by modulation of tissue and vessel signals using arterial spin labeling, while CBV(t) was measured with a susceptibility-based contrast agent. Baseline versus stimulation values in a region centered over the somatosensory cortex were: CBF=150+/-18 versus 182+/-20 mL/100 g/min, CBV(a)=0.83+/-0.21 versus 1.17+/-0.30 mL/100 g, CBV(t)=3.10+/-0.55 versus 3.41+/-0.61 mL/100 g, and CBV(a)/CBV(t)=0.27+/-0.05 versus 0.34+/-0.06 (n=7, mean+/-s.d.). Neural activity-induced absolute changes in CBV(a) and CBV(t) are statistically equivalent and independent of the spatial extent of regional analysis. Under our conditions, increased CBV(t) during neural activation originates mainly from arterial rather than venous blood volume changes, and therefore a critical implication is that venous blood volume changes may be negligible in BOLD fMRI.  相似文献   
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A randomized, placebo-controlled, double-blind study involving 60 subjects, aged 6-18 years old, was conducted over a period of 3 months to determine the effect of Pycnogenol® (a proprietary mixture of water-soluble bioflavonoids extracted from French maritime pine) on mild-to-moderate asthma. After baseline evaluation, subjects were randomized into two groups to receive either Pycnogenol® or placebo. Subjects were instructed to record their peak expiratory flow with an Assess® Peak Flow Meter each evening. At the same time, symptoms, daily use of rescue inhalers (albuterol), and any changes in oral medications were also recorded. Urine samples were obtained from the subjects at the end of the run-in period, and at 1-, 2-, and 3-month visits. Urinary leukotriene C4/D4/E4 was measured by an enzyme immunoassay. Compared with subjects taking placebo, the group who took Pycnogenol® had significantly more improvement in pulmonary functions and asthma symptoms. The Pycnogenol® group was able to reduce or discontinue their use of rescue inhalers more often than the placebo group. There was also a significant reduction of urinary leukotrienes in the Pycnogenol® group. The results of this study demonstrate the efficacy of Pycnogenol® as an adjunct in the management of mild-to-moderate childhood asthma.  相似文献   
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Few studies used paired kidneys for comparison between tacrolimus and cyclosporine in renal transplantation. Most of the published data used whole blood trough levels for drug monitoring. However, the use of limited sampling strategy and abbreviated formula to estimate the 12-h area under concentration-time curve (AUC(0-12)) allowed better prediction of drug exposure. Sixty-six first cadaveric renal transplant recipients receiving paired kidneys were randomized to receive either tacrolimus-based (n = 33) or cyclosporine microemulsion (Neoral)-based therapies (n = 33). Abbreviated AUC(0-12) was used for drug monitoring and dose titration. Mean follow-up duration was 2.8 +/- 2 years. The patient and graft survival were comparable. Fewer incidence of acute rejection was observed in tacrolimus group (15% vs. 27.3%) though the difference was not significant (P = 0.23). The absolute value and the rate of decline of creatinine clearance were both significantly better in tacrolimus-treated patients. Prevalence of hypertension, post-transplant diabetes mellitus, infection, and malignancy were similar in both groups. Prevalence of hypercholesterolemia (11/33 vs. 4/33) and gum hypertrophy (6/33 vs. 1/33) was more common in cyclosporine-treated patients (P = 0.04 in both parameters). This was the first prospective, randomized study with paired kidney analysis showing the renal function was significantly better in tacrolimus-treated patients than in cyclosporine-treated patients.  相似文献   
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